Electrical Engineering/velodyne ct150 15" sub

Question"Hi,I have a velodyne ct 150 15" subwoofer setup. I was using the setup for music an it was working fine for quite some time then it stopped outputting music coming from the sub I checked all connections an they were fine.power was on an still outputing music through the output jacks whether power is on or off ...i noticed that that amp area on the back of the sub was very warm so I cut the power off to the unit an let it set for about 15 mins with a blower fan cooling it when I cut it back on it was working again. after about another hour of use it cut off again an has not worked since.it still comes on plays music through the outputs the sub just does have sound coming from it I took a look inside the amp area an I didn't see or smell any kinda signs of shorting everything looks as the day it was made...I was thinking the speaker itself is blown it has recoil an doesn't really make noise when u flex the speaker any insight on this issue would be very helpful..."

AnswerI think you are on the right track.

It seems maybe the voice coil of the woofer has developed shorted turns causing the impedance to be too low thus sending the amplifier into overload. Do you think that could be the case?

If you have an ohmeter or access to one you could measure the dc resistance and whilst moving the cone in and out see if the resistance changes if the shorted coil is intermittent in nature.

There are many speaker shops around the country that will repair or replace the coils of the woofer.

Also, it is possible, now, the shorted coil wires have melted and the voice coil is open circuit thus not allowing any current to pass.